Practical Fig Culture in Arizona 17 



The temperatures during the 24 hours of the first and last dates 

 more nearly represent the average and usual winter weather, the 

 range being from 40° F. to 60° F. A study of these data shows the 

 temperature of the air to. vary from 32° F. to 65° F. during a period 

 of 8 hours on December 27, with very variable, and lower, degrees 

 during December 29, and from January 5 to January 13, 1913, 

 inclusive and respectively. The lowest temperature occurring during 

 the period was 16° F. The recurrence of low temperatures was 

 followed by periods in which all signs of frost disappeared. Alter- 

 nate freezing and thawing was undoubtedly responsible for the 

 severe injury occurring during the interval of 21 days included in 

 the chart. 



Attention is also directed to the hourly direction and velocity 

 of the wind. During many hours of dangerous temperatures the 

 velocity was greater than would warrant an attempt to heat an 

 orchard by the use of smudge pots. 



This period is the coldest that has occurred here since the record- 

 ing of temperature by modern methods, and as it is perhag^s the 

 coldest that will occur for many years, the conclusions drawn will 

 be a fair guide to the influence of temperature on fig production. 



Temperature has been the limiting factor in the determination 

 of the varieties we now recommend as hardy. These forms are 

 represented by both Capri and edible forms, and of the last named 

 one or more forms of e£;^h type of the severial groups endure the 

 conditions. This has made it necessary to study the entire field of 

 fig growing. 



The varieties but slightly damaged by the 1912-1913 freeze are 

 again in good condition and bearing fruit. The White Adriatic, 

 Black Ischia, and Madeleine have this year (1915) borne fair yields 

 of fruit, while the remaining varieties have produced none or a very 

 light crop. Observations show that dying-back of trees year after 

 year stunts them, while the very tender ones killed to the ground 

 each winter do not produce fruit. 



Yield of edible fruit.' — Accurate yields have not been available for 

 use except those computed from the data given in the 1900 and 

 1910 United States Census and those kept at the Experiment Station 

 Farm at phoenix. In 1899 the approximate yield per tree for 4,325 

 specimens of bearing age was 219 pounds. In 1910 it was 33 pounds 

 per tree. This yield, however, is the average for all bearing trees 

 of all ages and all varieties. A further calculation shows a range 

 from 1.8 pounds to 287.5 pounds per tree. Taking into account only 

 the yield from old and well established trees, the returns vary 



